Many different exhaust systems were tested (through Lafranconi) by both Tonti and Dutch tuner Jan Kampen. The 'Competizione' is the production version of the best overall. Ever see the race-system with its bent up boloney end?

That was a long time ago. Not surprised something better has been crafted since. What are the details on REX?

Meatier in the mid-range, but mostly, they're made of stainless - the LF Comps on my wife's bike are getting paper-thin in places.
REX stands for Ronnie Etter's eXhausts. A guy in Cape Town with a lot of sailing connections and a really nice guy, he had a Le Mans in the late 1970's and didn't like the way the stock pipes sounded or the way the LFs rusted away, so he made up a set of his own (they have a series of short outlet stubs inside the polished tip). His mates liked them so much they prevailed on him to make some more and he made another ten or so sets - and then he suddenly died. So Rex pipes are a VERY limited edition!
I was often in the "right place at the right time" and managed to score a pair of Rexs when a bike was traded by the local dealer; there is some suggestion that it was actually Ronnie's bike - and that the pipes were the original prototypes, as Ronnie's bike fell over and the pipes were slightly scratched - as are mine. I deliberately didn't repair them when I restored the bike - just gave them to the ceramic coaters.
I recently spotted another Australian bike with Rexs - a LM2 that was imported from South Africa years ago.

Pipes with boloney ends? You're thinking of Stucchi Luigi's system aren't you? Had a set on a couple of my bikes, but they rotted away quick-smart; sounded good though!

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